Encryption may include techniques for transforming information such that the information is unreadable to parties without possession of certain knowledge, such as an encryption key. Encryption may be used to protect different types of information. For instance, two parties seeking secure communication may encrypt transmissions of information with an encryption key to protect unauthorized parties from accessing the “clear text” (e.g., unencrypted) version of the information. Such an encryption key may be secret information previously exchanged by the parties in a secure manner. In other cases, encryption may be used as a mechanism to prevent unauthorized access to digital content, such as might be employed in a digital rights management scheme. For instance, electronic content (e.g., electronic representations of audio, video, or multimedia) may be encrypted to ensure that only authorized individuals may readily access the content. Examples of authorized individuals might include a customer that has purchased a license to view the content. In some implementations of digital rights management, a content license may include a cryptographic key for decrypting content to which the license corresponds. In this way, a customer that purchased rights to the content (and thus holds such license) may decrypt the content whereas unauthorized users (without access to such license) cannot decrypt the content.
The quantity of processing resources required to encrypt (or decrypt) a particular portion of content may depend on various factors. One of such factors may include the quantity of processing resources on hand. For instance, robust computing workstations might be able to encrypt or decrypt information at a rate faster than systems with less computing resources, such as a mobile handheld device. Another one of such factors may include the size of the information to be encrypted or decrypted. For instance, a given system may be able to encrypt or decrypt a single photo faster than it is able to encrypt or decrypt information with a much larger data footprint, such as a full length movie.